xref: /linux/arch/x86/include/asm/setup.h (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_SETUP_H
3 #define _ASM_X86_SETUP_H
4 
5 #include <uapi/asm/setup.h>
6 
7 #define COMMAND_LINE_SIZE 2048
8 
9 #include <linux/linkage.h>
10 #include <asm/page_types.h>
11 
12 #ifdef __i386__
13 
14 #include <linux/pfn.h>
15 /*
16  * Reserved space for vmalloc and iomap - defined in asm/page.h
17  */
18 #define MAXMEM_PFN	PFN_DOWN(MAXMEM)
19 #define MAX_NONPAE_PFN	(1 << 20)
20 
21 #endif /* __i386__ */
22 
23 #define PARAM_SIZE 4096		/* sizeof(struct boot_params) */
24 
25 #define OLD_CL_MAGIC		0xA33F
26 #define OLD_CL_ADDRESS		0x020	/* Relative to real mode data */
27 #define NEW_CL_POINTER		0x228	/* Relative to real mode data */
28 
29 #ifndef __ASSEMBLY__
30 #include <asm/bootparam.h>
31 #include <asm/x86_init.h>
32 
33 extern u64 relocated_ramdisk;
34 
35 /* Interrupt control for vSMPowered x86_64 systems */
36 #ifdef CONFIG_X86_64
37 void vsmp_init(void);
38 #else
39 static inline void vsmp_init(void) { }
40 #endif
41 
42 struct pt_regs;
43 
44 void setup_bios_corruption_check(void);
45 void early_platform_quirks(void);
46 
47 extern unsigned long saved_video_mode;
48 
49 extern void reserve_standard_io_resources(void);
50 extern void i386_reserve_resources(void);
51 extern unsigned long __startup_64(unsigned long physaddr, struct boot_params *bp);
52 extern unsigned long __startup_secondary_64(void);
53 extern void startup_64_setup_env(unsigned long physbase);
54 extern void early_setup_idt(void);
55 extern void __init do_early_exception(struct pt_regs *regs, int trapnr);
56 
57 #ifdef CONFIG_X86_INTEL_MID
58 extern void x86_intel_mid_early_setup(void);
59 #else
60 static inline void x86_intel_mid_early_setup(void) { }
61 #endif
62 
63 #ifdef CONFIG_X86_INTEL_CE
64 extern void x86_ce4100_early_setup(void);
65 #else
66 static inline void x86_ce4100_early_setup(void) { }
67 #endif
68 
69 #ifndef _SETUP
70 
71 #include <asm/espfix.h>
72 #include <linux/kernel.h>
73 
74 /*
75  * This is set up by the setup-routine at boot-time
76  */
77 extern struct boot_params boot_params;
78 extern char _text[];
79 
80 static inline bool kaslr_enabled(void)
81 {
82 	return IS_ENABLED(CONFIG_RANDOMIZE_MEMORY) &&
83 		!!(boot_params.hdr.loadflags & KASLR_FLAG);
84 }
85 
86 /*
87  * Apply no randomization if KASLR was disabled at boot or if KASAN
88  * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
89  */
90 static inline bool kaslr_memory_enabled(void)
91 {
92 	return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN);
93 }
94 
95 static inline unsigned long kaslr_offset(void)
96 {
97 	return (unsigned long)&_text - __START_KERNEL;
98 }
99 
100 /*
101  * Do NOT EVER look at the BIOS memory size location.
102  * It does not work on many machines.
103  */
104 #define LOWMEMSIZE()	(0x9f000)
105 
106 /* exceedingly early brk-like allocator */
107 extern unsigned long _brk_end;
108 void *extend_brk(size_t size, size_t align);
109 
110 /*
111  * Reserve space in the brk section.  The name must be unique within
112  * the file, and somewhat descriptive.  The size is in bytes.  Must be
113  * used at file scope.
114  *
115  * (This uses a temp function to wrap the asm so we can pass it the
116  * size parameter; otherwise we wouldn't be able to.  We can't use a
117  * "section" attribute on a normal variable because it always ends up
118  * being @progbits, which ends up allocating space in the vmlinux
119  * executable.)
120  */
121 #define RESERVE_BRK(name,sz)						\
122 	static void __section(".discard.text") __used notrace		\
123 	__brk_reservation_fn_##name##__(void) {				\
124 		asm volatile (						\
125 			".pushsection .brk_reservation,\"aw\",@nobits;" \
126 			".brk." #name ":"				\
127 			" 1:.skip %c0;"					\
128 			" .size .brk." #name ", . - 1b;"		\
129 			" .popsection"					\
130 			: : "i" (sz));					\
131 	}
132 
133 /* Helper for reserving space for arrays of things */
134 #define RESERVE_BRK_ARRAY(type, name, entries)		\
135 	type *name;					\
136 	RESERVE_BRK(name, sizeof(type) * entries)
137 
138 extern void probe_roms(void);
139 #ifdef __i386__
140 
141 asmlinkage void __init i386_start_kernel(void);
142 
143 #else
144 asmlinkage void __init x86_64_start_kernel(char *real_mode);
145 asmlinkage void __init x86_64_start_reservations(char *real_mode_data);
146 
147 #endif /* __i386__ */
148 #endif /* _SETUP */
149 #else
150 #define RESERVE_BRK(name,sz)				\
151 	.pushsection .brk_reservation,"aw",@nobits;	\
152 .brk.name:						\
153 1:	.skip sz;					\
154 	.size .brk.name,.-1b;				\
155 	.popsection
156 #endif /* __ASSEMBLY__ */
157 #endif /* _ASM_X86_SETUP_H */
158